This invention relates to a fluid dispensing tools or tool assembly of the general type disclosed in U.S. Pat. No. 5,560,407, No. 6,257,285 and No. 6,298,886 which issued to the Assignee of the present invention. Such tools are commonly used on a motor vehicle assembly line for evacuating and charging an air conditioning system and a coolant system for the vehicle and are connected by flexible lines to a control unit which provides for evacuating the system to a predetermined evacuation pressure, tests the system for leaks and then charges the system with a selectable predetermined volume of liquid such as liquid refrigerant or coolant.
The present invention is directed to an improved fluid dispensing tool assembly of the general type disclosed in the above identified patents and which is ideally suited for testing and charging or filling a fuel storage tank in a motor vehicle on the vehicle assembly line. Such a fuel storage tank commonly includes a fill tube which extends upwardly from the tank to a fill tube neck portion which has internal threads for receiving a removable fuel sealing cap. The fluid dispensing tool assembly of the present invention releasably and positively grips the inner surface of the fill tube neck portion and then forms a fluid-tight seal with an outer end flange on the neck portion. The tool assembly also provides for conveniently holding and handling the tool assembly in an ergonomic manner and for operating the controls of the tool assembly. The tool assembly further provides for substantial durability and for convenient servicing.
In accordance with one embodiment of the invention, the above features are provided by a tool assembly including a body defining a fluid or fuel supply passage with an air actuated control valve and extending from an inlet to an outlet tube having an axis perpendicular to the axis of the inlet. An annular clamping piston surrounds the outlet tube and is effective to expand a set of arcuate clamping jaws outwardly into engagement with the neck portion of the fill tube. An annular sealing piston surrounds the clamping piston and carries resilient sealing rings for forming a fluid-tight seal with an outer end portion of the fill tube. The main fluid control valve and the annular pistons are each actuated by pressurized air supplied through passages within the body. An axially movable pin is supported by the body outboard of the sealing piston for detecting the presence of the fill tube flange and for actuating a proximity switch after the outlet tube has been properly positioned on the fill tube. The fluid supply and air actuating lines connect to the tool assembly by fittings having corresponding axes perpendicular to the axis of the outlet tube, and the body is supported by an upper horizontally extending handle projecting from a body portion having thumb actuated switches to control the cycle of operation of the tool assembly.